Studies On Voltage Stability Of A Regional Power Grid Of Xinjiang Containing Wind Power

Along with the development of wind generating technology and the Government's support for generating by new energy, the penetrating wind power is more and more. So the impact of wind power accessing to power system on the voltage stability is growing. Especially the region, where the wind resource is quite abundant, often is at the edge of the main power grid, the distance of transmission is long. And when the regional loads is relatively scattered and network structure is relatively weak, the impacts of grid-connected wind farms on voltage stability of the regional grid become more significant.This paper establish the four-component model of wind speed, the model of wind turbine blade and its driving mechanism, the model of control system, the static and transient model of the general asynchronous wind generators and doubly-fed asynchronous wind generators. Someone power grid in model Xinjiang is established on PSASP simulation platform. The steady-state voltage distribution is simulated before and after the wind farm accesses to the system. The PV curves and margins are applied to analyze the static voltage stability of wind farms adopting general asynchronous wind generators and doubly-fed asynchronous wind generators. The network characteristics of the established regional power grid are analyzed. The Time-domain simulation method is applied to analyze the transient voltage stability after wind farms adopting general asynchronous wind generators and doubly-fed asynchronous wind generators, analyze the transient voltage stability when there are load fluctuation of wind farm, ramp wind and gust wind. Finally, the impact of SVC and STATCOM on the voltage stability of power system containing wind farms which adopt general asynchronous generators is discussed.The simulation results indicate that wind farms which adopt general asynchronous generators access to the regional power grid can improve the status which is the steady-state voltage is high, reduce the power system loss. The DFIG needn't absorb reactive power from the system, and it can regulate reactive power to some extent. So the wind farm adopting DFIG is better than the wind farm adopting general asynchronous generator either static or transient voltage stability, this is agreement with the conclusion from the simulation results. And SVC, STATCOM dynamic reactive compensations can improve the transient voltage stability of wind farm adopting general asynchronous generator.